The present invention relates to a straw-insertable lid for a paper cup, and more particularly to a straw-insertable lid for a paper cup for accommodating beverages therein such as tea, a soft drink, fruit juice or the like, a sherbet-like beverage of any of these beverages, or the like singly or together with crushed ice, such a beverage being served to customers with or without a snack such as a hamburger, fried chicken, a sandwich, or the like at fast-food restaurants specializing in such as hamburgers, fried chicken, and sandwiches and at snack corners of department stores, supermarkets, convenience stores, and the like.
A conventionally known straw-insertable lid for a paper cup of this type is formed of a plastic and, as shown in FIG. 3, comprises a top plate portion 22 for covering an opening at an upper end of a paper cup 21; a peripheral sidewall portion 23 which is disposed around an outer peripheral edge of the top plate portion in such a manner as to project downward and is fitted with an outer periphery of a rim of the paper cup; and cross-shaped slits 25 provided in the top plate portion 22 and adapted to allow a straw 24 to be inserted therethrough.
With such a conventional lid, there has been a problem in that since they are formed of plastics, if the lids after being used are disposed of by being dumped as rubbish, they do not decompose at all and constitute a major source of environmental destruction.
According to the Aug. 29, 1989, issue of the noted American economic journal "Fortune", the total volume of plastics produced annually in the United States reaches about 27 million tons. The journal also reports that the volume of plastics dumped accounts for almost 25% of the total volume of rubbish, the figure being the second largest next to paper which accounts for 40%. Although 80% of such rubbish is disposed of by dumping, dumping sites are said to become full in 10 to 20 years. For this reason, during the last two years, more than 800 bills for controlling rubbish, centering on plastics, were proposed in various municipalities at the local government level. Stipulations for control which these bills called for, among others, include the levying of a tax on packages and permission of disposal of only the rubbish whose matter decomposition rate exceeds a certain level.
In addition, in the case of the above-described conventional lid, there is a possibility that the cross-shaped slits for insertion of a straw therethrough that are provided in the top plate portion of the lid can be inadvertently ripped large by the insertion of the straw therethrough. Hence, there has been the problem that if the paper cup falls by accident or by being carelessly handled, its content is spilt through the slits ripped large, as described above.
Furthermore, with the above-described conventional lid, there has been another drawback in that if the manufactured state of the lid is poor by any slightest degree, the lid easily comes off the paper cup since it is made of a plastic.
Moreover, with the above-described conventional lid, which is formed of a plastic, there has been still another drawback in that since there is a gap in the cross-shaped slits for the insertion of the straw, if the paper cup falls by being carelessly handled or is shaken, its content is spilled through the gap of the slits.